People will choose larger portions of food if they are labelled as being "healthier," even if they have the same number of calories, according to a new study from the INSEAD Social Science Research Center in France.
The researchers found out, that people think that healthier food is lower in calories. This misconception can lead to them eating larger portion sizes of so-called healthy foods, and therefore more calories.
Safefood, a government agency in Ireland, commissioned the study, led by Barbara Livingstone, a professor at the University of Ulster. Dr. Cliodhna Foley Nolan, the director of Human Health and Nutrition at Safefood, said that the portion sizes of food have become larger over the years, and Safefood wanted to see whether health and nutrition claims had any influence.
The researchers asked 186 adults to assess the appropriate portion sizes of foods. Given a bowl of coleslaw, the participants served themselves more of the coleslaw labeled "healthier" than the coleslaw labeled "standard." For instance, obese men served themselves 103 g of healthy coleslaw and 86 g of standard coleslaw.
In reality, the healthy-labeled coleslaw had just as many calories - 941 kilojoules (or 224 calories) for every 100 grams - as the "standard" coleslaw, which had 937 kilojoules (or 223 calories).
Additionally, people tended to underestimate how many calories were in a serving for the "healthier" coleslaw. The participants most often thought the "healthier" coleslaw contained 477 kilojoules, or 113 calories. In contrast, they were not far off in estimating the calories in the "standard" coleslaw.
Source: INSEAD Social Science Research Center